Purpose: To evaluate the association of severe periodontitis with overweight and obesity. Material and Methods: Full-mouth periodontal examination was performed on a random sample of 80 obese, 69 overweight and 87 normal-weight individuals (≥ 18 years). Severe periodontitis was defined using the Centers for Disease Control and Prevention - American Academy of Periodontology (CDC-AAP) case classification. Weight (kg) and height (m) were measured by a single examiner, body mass index (BMI) was calculated, and the subjects were classified as normal range, overweight and obese according to World Health Organization definitions. Interviews using a structured questionnaire were performed to collect data on demographics as well as socioeconomic and health status. Chi-squared and logistic regression tests were used to assess the association between severe periodontitis and obesity (p ≤ 0.05). Results: Although severe periodontitis was significantly associated with obesity (OR = 3.25, 95% CI = 1.27-8.31, p = 0.01), it was not associated with overweight (p = 0.59). Conclusions: In the present study, severe periodontitis was associated with obesity but not with overweight. Patients diagnosed with obesity should be referred for periodontal evaluation. Keywords: cross-sectional study, obesity, periodontal disease, risk factors